condition mean min max ZT0-3 1.6574775000000002 1.461425 1.8535300000000001 ZT4-7 1.484745 1.484745 1.484745 ZT8-11 1.109601 1.109601 1.109601 ZT12-15 0 0 0 ZT16-19 1.6032899999999999 1.6032899999999999 1.6032899999999999 ZT20-23 1.243613 1.243613 1.243613